1. Field of the Invention
The present invention relates to a touch panel device in which information are input by an input pen onto a touch panel that is provided in front of a flat display such as a plasma display panel, etc.
2. Description of the Related Art
In recent years, the touch panel device has been spread as the inputting means for various information processing devices.
This touch panel device senses a coordinate of a touch position on the touch panel, and inputs various information into the information processing device in response to the touch position. Various systems have been proposed.
Out of the touch panel devices, there is the ultrasonic surface acoustic wave system that senses the coordinate of the touch position on the touch panel by utilizing the ultrasonic wave.
FIG. 25 is a schematic view showing the touch panel device in the conventional art utilizing the ultrasonic surface acoustic wave system.
In FIG. 25, the touch panel device comprises an X-side reflection array 2A on the transmitter side, which is provided horizontally to a lower edge portion of a touch panel 1; an X-side transmitter 2B arranged on the lower right-hand corner of the touch panel 1 and connected to the X-side reflection array 2A; an X-side reflection array 3A on the receiver side, which is provided horizontally to an upper edge portion of the touch panel 1 so as to oppose to the X-side reflection array 2A; an X-side receiver 3B arranged on the upper right-hand corner of the touch panel 1 and connected to the X-side reflection array 3A; a Y-side reflection array 4A on the transmitter side, which is provided vertically to a left-side edge portion of the touch panel 1; a Y-side transmitter 4B arranged on the upper left-hand corner of the touch panel 1 and connected to the Y-side reflection array 4A; a Y-side reflection array 5A on the receiver side, which is provided vertically to a right-side edge portion of the touch panel 1 so as to oppose to the Y-side reflection array 4A; and a Y-side receiver 5B arranged on the upper right-hand corner of the touch panel 1 and connected to the Y-side reflection array 5A.
In this touch panel device, the ultrasonic wave that is output from the X-side transmitter 2B is oscillated upward in the vertical direction from respective positions, which are provided along the axis direction (X direction) of the X-side reflection array 2A on the transmitter side, to the X-side reflection array 3A on the receiver side. Then, the ultrasonic wave that is received at respective positions, which are provided along the axis direction (X direction) of the X-side reflection array 3A on the receiver side, is input into the X-side receiver 3B.
Also, the ultrasonic wave that is output from the Y-side transmitter 4B is oscillated rightward in the horizontal direction from respective positions, which are provided along the axis direction (Y direction) of the Y-side reflection array 4A on the transmitter side, to the Y-side reflection array 5A on the receiver side. Then, the ultrasonic wave that is received at respective positions, which are provided along the axis direction (Y direction) of the Y-side reflection array 5A on the receiver side, is input into the X-side receiver 5B.
Then, identification of the touch position on the touch panel 1 is carried out as follows. For example, when any position Pxe2x80x2 on the touch panel 1 is touched as shown, the ultrasonic waves that are oscillated respectively from the X-side reflection array 2A and the Y-side reflection array 4A on the transmitter side are blocked by the finger, the input pen, or the like, that touches the touch panel 1. Therefore, the positions (x coordinate and y coordinate) on the X-side reflection array 3A and the Y-side reflection array 5A on the receiver side can be detected based on change (attenuation) of the ultrasonic signals that are input into the X-side receiver 3B and the X-side receiver 5B.
This ultrasonic surface acoustic wave system touch panel device has the characteristic such that it is less affected by the temperature and the humidity and is excellent in the durability.
However, the ultrasonic surface acoustic wave system touch panel device in the conventional art has problems such that, as shown in FIG. 25, the transmitter-side reflection array and the receiver-side reflection array must be arranged on four sides of the touch panel respectively and in addition, in order to reduce the detection error by increasing the detection precision of the touch position, the size of the device is increased and the detection precision has a limit since acoustic transmitter portions and receiver portions must set finely in the transmitter-side reflection array and the receiver-side reflection array respectively.
Also, the ultrasonic surface acoustic wave system touch panel device in the conventional art identifies the touch position Pxe2x80x2 by sensing the vibration caused by the acoustic wave and propagated over the touch panel 1. Therefore, if this touch panel device is fitted to the plasma display panel (PDP), for example, there is such a possibility that the vibration generated in the touch panel 1 by driving the PDP is sensed as the noise and thus the error is caused in the detection result.
The present invention has been made to overcome the problem that is included in the above touch panel device in the conventional art.
That is, it is an object of the present invention to provide a touch panel device capable of sensing a touch position by a simple configuration with high precision.
In order to achieve the above object, according to the first invention, there is provided a touch panel device for sensing a touch position on a touch panel provided in front of the flat display device, comprising sound collecting members arranged at least any two different locations of edge portions of the touch panel, for sensing a sound signal propagated through a space; an input pen containing a signal oscillating member, for oscillating an oscillated signal that is output from the signal oscillating member from a top end portion; and a coordinate position calculating member for calculating a coordinate of the touch position of the input pen on the touch panel by calculating distances between the sound collecting members and the touch position of the input pen on the touch panel, based on the sound signal oscillated from the input pen to be sensed by the sound collecting members; wherein the sound collecting members have a sound collecting directivity characteristic that can cover an overall surface of the touch panel in response to fitted positions of the edge portions of the touch panel.
According to the touch panel device of the first invention, when the top end portion of the input pen touches the touch panel, the sound signal such as the acoustic wave output from the signal oscillating member built in the input pen is oscillated from the top end portion of the input pen to propagate through the space along the front surface of the touch panel, and then is sensed by the sound collecting members, that are fitted to at least two different locations of the edges portions of the touch panel, respectively.
Then, the coordinate position calculating member calculates the distances between the sound collecting members and the touch position on the touch panel, at which the sound signal is oscillated, based on the sound signal sensed by the sound collecting members and then calculates the X, Y coordinate values on the touch position of the touch panel based on respective calculated distances to identify the touch position of the input pen.
Then, the sound collecting members that sense the sound signal oscillated from the input pen to identify the touch position have the sound collecting directivity characteristic to cover the overall surface of the touch panel, for example, 90 degree if the sound collecting members are arranged at the corner positions of the edge portions of the touch panel or 180 degree if the sound collecting members are arranged in the middle positions of the edge portions of the touch panel. Therefore, even if the input pen touches any position on the touch panel, the sound signal oscillated from the input pen can be sensed by the sound collecting members.
As described above, according to the touch panel device of the first invention, the touch position on the touch panel can be identified only by arranging the sound collecting members at two locations of the edge portions of the touch panel. In addition, since the sound collecting members have the sound collecting directivity characteristic to cover the entire surface of the touch panel in answer to the fitted positions on the edge portions of the touch panel, the sound signal oscillated by the input pen can be sensed firmly by the sound collecting members even if the input pen touches any position on the touch panel. As a result, it is possible to sense the touch position by a simple configuration with high precision.
In addition, since the identification of the touch position is performed by sensing the sound signal, that is oscillated from the input pen to propagate through the space, by virtue of the sound collecting members, there is no possibility that the vibration caused by driving the display device into which the touch panel is incorporated is detected as the noises rather than the case the identification of the touch position is performed by sensing the vibration propagated through the touch panel, like the conventional art. Thus, it is possible to perform the sensing of the touch position with high precision.
In order to achieve the above object, according to the second invention, in addition to the configuration of the first invention, the sound collecting members are microphones.
According to the touch panel device of the second invention, the sound signal such as the sound wave, the ultrasonic wave, etc., that is oscillated from the signal oscillating member in the input pen, can be sensed by the microphones acting as the sound collecting members.
In order to achieve the above object, according to the third invention, in addition to the configuration of the first invention, the sound collecting members are arranged at corner positions of the edge portions of the touch panel and have a 90-degree sound collecting directivity characteristic in a flat plane that is parallel to the touch panel.
According to the touch panel device of the third invention, when the sound collecting members are arranged at the corner positions of the edge portions of the touch panel, the sound collecting members have the 90-degree sound collecting directivity characteristic in a flat plane that is parallel to the touch panel since the range of the touch panel extending in the sound collecting direction of the sound collecting members is in the range of 90 degree. Therefore, even if the input pen touches any position on the touch panel, the sound signal oscillated from the input pen can be sensed without fail by the sound collecting members.
In order to achieve the above object, according to the fourth invention, in addition to the configuration of the first invention, the sound collecting members have a horn member to form an opening portion that is opened forward by an angle of 90 degree.
According to the touch panel device of the fourth invention, the sound collecting directivity characteristic of the sound collecting members can be set to 90 degree in the flat plane that is parallel to the touch panel by the horn member that forms the opening portion opened forward by the angle of 90 degree
In order to achieve the above object, according to the fifth invention, in addition to the configuration of the first invention, the sound collecting members are arranged at middle positions of the edge portions of the touch panel and have a 180-degree sound collecting directivity characteristic in a flat plane that is parallel to the touch panel.
According to the touch panel device of the fifth invention, when the sound collecting members are arranged in the middle positions of the edge portions of the touch panel, the sound collecting members have the 180-degree sound collecting directivity characteristic in the flat plane that is parallel to the touch panel since the range of the touch panel extending in the sound collecting direction of the sound collecting members is in the range of 180 degree. Therefore, even if the input pen touches any position on the touch panel, the sound signal oscillated from the input pen can be sensed without fail by the sound collecting members.
In order to achieve the above object, according to the sixth invention, in addition to the configuration of the first invention, the signal oscillating member is composed of a piezoelectric loudspeaker containing a piezoelectric element.
According to the touch panel device of the sixth invention, the sound signal such as the acoustic wave, the ultrasonic wave, or the like can be oscillated from the piezoelectric loudspeaker containing the piezoelectric element.
In order to achieve the above object, according to the seventh invention, in addition to the configuration of the fifth or sixth invention, the input pen has an opening portion formed at a top end portion, and the sound signal that is output by the signal oscillating means being built in the input pen is oscillated from the opening portion to have a directivity of 360 degree around a penholder of the input pen.
According to the touch panel device of the seventh invention, when the input pen touches the touch panel, the sound signal being output from the signal oscillating means built in the input pen is oscillated from the opening portions formed at the pen point portion of the input pen around the penholder of the input pen to have the directivity of 360xc2x0. Therefore, everywhere the input pen touches the touch panel, the sound signal can be sensed by the sound collecting members and thus the touch position can be identified without fail.
In order to achieve the above object, according to the eighth invention, in addition to the configuration of the first invention, an inner wall surface of the pen point portion of the input pen is formed as a circular cone shape such that a diameter is reduced smaller toward a top end side, an inside of the circular cone shape is communicated to an outside via an opening portion that is formed on a top end of the input pen, and the sound signal output from the signal oscillating means via the inside of the circular cone shape formed at the pen point portion of the input pen is oscillated from the opening portion.
According to the touch panel device of the eighth invention, the inner wall surface of the pen point portion of the input pen, through which the sound signal being output from the signal oscillating means built in the input pen is passed, is formed as the circular cone shape. Therefore, the sound signal being oscillated from the opening portion formed at the top end can have the non-directivity.
In order to achieve the above object, according to the ninth invention, in addition to the configuration of the first invention, a top end of the input pen is formed like a spherical shape, and opening portions that oscillate the sound signal being output from the signal oscillating means to an outside are formed on an outer peripheral surface of the input pen in rear of the top end being formed like a spherical shape.
According to the touch panel device of the ninth invention, since the top end of the input pen is formed like the spherical shape, it can be prevented that the surface of the touch panel is damaged when the input pen touches the touch panel. In addition, since the opening portions formed to oscillate the sound signal being output from the signal oscillating means to the outside are formed on the outer peripheral surface in rear of the spherical top end of the input pen, it can be prevented that the oscillation of the sound signal is disturbed by blocking the opening portions when the input pen touches the touch panel.
In order to achieve the above object, according to the tenth invention, in addition to the configuration of the first invention, the input pen has a battery member that supplies a drive power to the signal oscillating means therein, a holder for holding the input pen is prepared, a charging member is built in the holder, and the battery member of the input pen is charged by the charging member when the input pen is held by the holder.
According to the touch panel device of the tenth invention, if the input pen is held in the pen holder when the input pen is not used, the battery member built in the input pen can be charged by the charging member built in the pen holder.
In order to achieve the above object, according to the eleventh invention, in addition to the configuration of the first invention, an oscillating signal absorbing member for absorbing the sound signal oscillated from the signal oscillating means is provided to edge portions of the touch panel.
According to the touch panel device of the eleventh invention, the sound signal, that reaches the edge portions of the touch panel other than the portion to which the sound collecting members are provided, out of the sound signal oscillated from the signal oscillating means in the input pen can be absorbed by the sound signal absorbing member without reflection. Therefore, the noises caused by the reflected wave can be prevented from being sensed by the sound collecting members, and thus the touch position can be identified with high precision.
In order to achieve the above object, according to the twelfth invention, in addition to the configuration of the first invention, the flat display device consists of a plasma display panel.
According to the touch panel device of the twelfth invention, the touch position of the input pen can be sensed on the display screen of the plasma display panel.